Dry-kiln.



0. A. WENBORNE.

DRY KILN.

APPLIOATION FILED AUG. 29, 1910.

Patented Jan. 9,1912.

k Q 5% L I w n I 3Q Q WP Q v N Q r QR a ig To all whom it may concern:

CHARLES A. wnnnomm, orcHIcAeo, ILLIYNOIS.

. DBY-KILN."

speolflcationot Letters Patent.

Pate'nted Jan]..9,.1912.

Application filed August 29, 1910. SerialNo, 575,421. I

Be it known that 1, CHARLES America, and a resident of Chicago, county of Cook, State of Illinois, have invented certain new and useful Improvements in Dry-Kilns, of which the following is a specification.

The main object of this invention is to provide a kiln wherein substances or 'arti-' ficial surfaces can be exposed to the dry ing or oxidizing or other Influence of heated air traveling horizontally, or'more horizontally than vertically. Suchkiln. is especiallyv deslrable where the substances or surfaces are fluid or vlscous, or where the-supports would offer too great an lnipedlment'to alr traveling vertically or nearly so; also where solid materials, coated or uncoated, areof such dimenslons as would, in a vertically movlng air current, cause eddies to form over them, and thus prevent uniformity of drying or of oxidizing effect. To provide such a kiln, I have applied largely the'principles underlying the form of kiln invented by myself, and patented to me April 20th,

1909, Patent No. 918,621, in which, however,

the movement of the air is more vertical than horizontal, and which form of kiln is in successful operation at the present time. But to make a kiln of this type work successfully with an air movement that is more horizontal than .vertical, the construction must be quite different from that described in my said patent- A specific construction embodying my present invention is illustrated in the accompanying drawings, in which Figure 1 is a transverse section,-more or less diagrammaticmf a drying kiln inwhich the air current in the-drying chamber is substantially horizontal, and also showing an arrangement of parts which is suitable for use in connection with a series of drying chambers. Fig. '2 is an enlarged sectional detail, showing the arrangement of pipes in the heating coil of the heating chamber, and also showing the shape of the deflector bars or slats, of which the partition separating the heating and drying chambers is made up.

Fig. 3 .is' a fragmentary detail in perspective,

showing the construction of the partition separating the drying and cooling chambers. Fig-Li's a detail in perspective, h

A. WEN HORNE, a citizen of the United States of ing the shapeof the-bar's. or'slat's in the partition between the: heatingand' drying chambers, and also showing "the shape of the spacer blocks which are placed between these slats attheir: ends. Fig. 5 shows cor-. responding details of theslats and blocks in the. partition between the drying and cooling chambers. In the form shown in means. of a second floor 1, and vertical partitions 2 and 3, to form a drying chamber A,

- a heating chamber B, a cooling chamber C,

and return air passage D below the drying chamber, connecting the cooling and heating chambers, these chambers and passage being all co-extensive with each other lengthwise of the kiln. The dimension herein referred to as the length of the kiln is that which is at right angles to the plane of Fig. 1. Access to the drying chamber is had through a door 4, indicated in dotted outline in Fig. 1. and this door should also be capable of being closed airtight, so that there can be no leakage of air through the walls of the kiln to disturb its proper opera? tion. In the specific design'shown in Fig. 1, the kiln is provided with two drying chambers A, and the heating chamber B is common to both. This arrangement is not essential to the carrying out of this invention, but is shown in the drawings with the view to illustrating the manner in which a kiln having a series of drying chambers might be constructed in installations where the drying chambers. would be operated 7 I the drawings, the 'kilncomprises a rectangular building, which has airtight walls, floor and ceiling, and which has its interior subdivided by simultaneouslv -and under likecondition In most installations, it may be preferred to have each unit, comprising a drying chamber A, a heating chamber B, and a cooling chamber 0, independent of any of the other drying chambers.-

The walls 2 and 3 arepreferably built up I i of horizontally disposed slats supported by suitable uprights-and spaced apart vertically to provide long horizontal slits or air passages-between them. .In the form shown,

the partition 2 is-made up of slats 5, which are of inverted V-shape incross-section, and so assembled-that the passages between them will be of tortuous form so as to prevent the radiation of heat from the heating'mean in,

' rather than to cut off radiated heat. The shape of the slats 8 and spacer blocks 9'is,

*that the sectional shape of the slats is determinedwith a view to directing the-air downwardly into 'the cooling chamber C,

illustrated in Fig. 5.

In the heating chamber B, there is arranged a steam coil 10, which comprises a series of horizontally disposed pipes connected together at their ends, to form a .con: tinuous coil extending-throughout the length of the chamber B. At the lower part of the chamber B, the pipes of the coil 10 are close together, and they are spaced apart at gradually increasing intervals toward the upper part ofthe chamber. The height to which the coil 10 is carried depends upon conditions which might vary considerably in different installations, as for instance, the width of the'heating chamber A, the character of the substances to be treated and the range of temperature within which the kiln.

is to be operated, but in most cases, it is not necessary nor desirable to carry the heating coil throughout the entire height .of the a chamber B, for the reason that the air heated by the coil tends to rise straight upward, and this tendency should be so regulated with respect, to the horizontal draft induced by the cooling chamber as to insure the uniform distribution of heat throughout the drying chamber, as will hereinafter appear. In most cases, it is preferred to stagger the pipes of the heating coil, 'asillustrated.

In the cooling chamber there" is provided a condenser, comprising a system of cooling pipes which may be in the form of a' coilsimilar to that of the steam pipes in. the heating chamber, although I prefer to use a pair' of horizontally disposed manifolds or headers 11 and 12, located respectively at the top and bottom of the outer wall '13 of the cooling chamber, and to connect these by a series of suitably spaced vertical pipes 14. Throughout the lower part of the cooling chamber C is arranged a coil of horizontally disposed pipes 15, arranged in staggered relation to each other, and connected in succession at their ends to form a con-.-

tinuous coil, the outlet end being connected with the lower manifold 12, and the inlet end being connected with a source of 'cold water or other-cooling medium, and con-.

trolled by a valve 16. The outlet of the cooling system is at the upper part of the chamber C, and is controlled by a valve 17. Valves18 and 19 control the flow. of heat-j ingmedium in the heating coils 10.

he-floor at 20 below the cooling coil 15 is inclined downwardly in the. direction of the air current, and is provided with a gutter 21, the surfaces at each "side of the gutter 21 being substantially in linewith each other, so that the air flowing along them,

meets with no obstacle or sudden enlargement of the passage, and thus avoids the formation ofeddies.

, When there are two drying chambers A,

as in Fig. 1, a low partition 22 is provided at the bottom of the chamber B to prevent conflict of the air currents enterin said chamber from the two air passages and there is also a partition 23 which extends downward from the ceiling of the chamber B so as to separate the two air currents'at the upper part thereof, which respectively flow into the two chambers A. l

The specific construction illustrated in, Fig. 1, in which the kiln is made up of a series of units having common heating or drying chambers, is designed for cases where the nature of the materials to be dried permits such a construction, and this arrangement is shown merely by way of illustration,

as it will be understood that in most installations, it would be preferable to have each drying room independent of any other.

The operation of the device shown is as follows :Before loading the kiln, it is well to turn on the steam or other heating medium for a short time, so as to warm up all of the component parts of the kiln, and have a reserve ofhot air in the heating chamber.

, After the kiln is loaded, its door is tightly closed. Before admittin the cooling medium t0 the condenser, sufiicienttime should be allowed for the substances or surfaces'to be treated to warm up to thetemperature ofthe dry room. This time allowance will vary greatly 'with different substances, being dependent upon the percentage of'moisture whichthey contain,' their porosity, or-

in cases of coated surfaces, with the ratio of the volatile matter incorporated with the' coating. Thus, with'diiferent materials to be treated, tests must be made to determine the time necessary for the preliminary warming, the time required for drying, and the temperature that can be applied most advantageously and safely. -When the proper method of treatmentis once determined for any one substance, it may be used as a guide for future operations, and will always produce the same results for the reason that the kiln is tightly closed, and

the variable atmospheric influences on the outside cannot affect the workwhich 1s be:

' tween the pipes ofthe coil into the cham-.

ing done within. When the preliminary warming is finished, the condenser system is brought into action by starting the flow -of'water through it. .The cold water in the condenser cools the surrounding air, which therefore contracts, and falls to the bottom of the cooling chamber C, .and passes beber D. The heating coil expands the air around it. This expanded air, becoming lighter, rises. In'this way a circulationis set up which continues as long as the con-' denser is operation. The contraction of the air inthe chamber C takes place throughout that entire chamber, but is in tensified at the lower part thereof by the coil 15. Thus, there is a tendency to form' a partial vacuum at, all parts of the condensing chamber C, which, however, is continuously off-set by the heated air flowing in to said chamber from the" chamber A. This tendency creates a horizontal draft throughout the height of the chamber A, I

which causes the heated air from the chamber B to flowthrough the openings inthe partition 2. The fact that the air, on becoming heated, tends to rise, insures a uniform distribution of the aircurrent throughout the height of the partition 2, and the combined-result is a tendency of the air tofiowcontinuously in a substantially horizontal direction across the chamber A. As

this influence is the same throughout the length of the chamber A, the drying action is uniform at all parts of the chamber A. The moisture, which is condensed upon the condenser through the cooling of the air in v the cooling chamber, drips down on to the inclined floor 20, and runs into the gutter which slopes toward one end of the kiln, and terminates in a suitable drip pipe, not shown. v

The surfaces of the slats .of the partition 2 are all painted a dull black, so that they will absorb instead of reflecting the heat waves, and thus radiation from the heating means into the drying chamber is prevented, and a uniform temperature throughout the drying chamber is insured. This fact also makes it possible to dry surfaces coated with varnishat an unusally high temperature without blistering the varnish.

In some cases, it may be preferred to augment the air current with certain fixed conditions, as to the temperatures of the heating and cooling chambers, and this may be accomplished by mechanical means for intensifying the draft in the passage C, and represented diagrammatically in Fig. 1 by the representation of a fan 24, which, it

will be understood, is power driven.

Although but one specific embodiment of this invention is herein shown and described, itwill be understood that. numerous details of the construction shown may be.

-- chamber, a heatin .side of said drying chamber, a cooling altered or omitted. without departing from the spirit of this invention, as defined by the following claims.

I claim 1. A drying -kiln, comprising a drying chamber located at one chamber located at the opposite side of said drying chamber, partitions separating said chambers and containing distributed apertures'arranged to permit air to flow from saidheating chamber to said cooling chamber in a uniformly distributed current throughdut the area of said drying chamber, a return air passage connecting said cooling chamber with said heating chamber, heating means in said heating chamber, and cooling means in said cooling chamber, said heating and cooling means being located so as to produce by gravity :1 horizontal flow of air in said drying cham- 2. A drying kiln, comprising a drying chamber, a heatin chamber located at one side of said drying chamber, a coolin chamberlocated at the opposite side of sai drying chamber, partitions separating said chambers and containing distributed apertures arranged to permit air to flow from said heating chamber to said cooling chamber in auniformly distributed. currentthroughout the area of said drying chamber, a return air passage connecting said cooling chamber with said heating chamber, heating means in said heating chamber, cooling means in said cooling chamber, and said partitionbetween said heating and drying chambers being constructed to prevent the radiation of heatfrom said heating means into said drying chamber.

3. A drying kiln, comprising a drying chamber, a heatin chamber located at one :side of said drying chamber, a cooling chamber located at the opposite side of said drying chamber, partitions separating said chambers and containing distributed apertures arranged to permit air to flow from said heating chamber to said cooling chamber in a uniformly distributed current throughout the area of said drying chamber, a return air passage connecting said cooling chamber with said heating chamber,

chambers and containing distributed apertures arrangedto permit air to flow from said heating chamber to said cooling chain ber in a uniformly distributed current throughout the area of said drylng chamber,

a return air passage below sa1d drying side of said drylng chamber, a cooling, chamber located at the opposite side of said drying chamber, partitions separating said chambers and containing distributed aper-- tures arranged to permit air to flow from said heating chamber to said cooling chamber in a uniformly distributed current throughout the area ofsaid drying chamber, a return air passage below said drying chamber connecting said cooling chamber said heating chamber, heating means in said heating chamber, cooling means in said 0001- ing chamber, and said partition between said drying and coolin chambers being made up of horizontally dlsposed slats placed substantially in parallel relation and inclined downward toward said cooling chamber.

6.LA drying kiln, comprislng a drying chamber, a heating chamber located at one side of said drying chamber, a cooling chamber located at the opposite side'of said drying chamber, partitions separating sald chambers and containing distributed apertures arranged to permit air to flow from said heating chamber to said cooling chamber in a uniformly distributed current throughout the area of said dryin chamber, a return air passage below sai drying chamber connecting said cooling chamber with said heating'chamber, heating means in said heating chamber, and cooling means in said cooling chamber and extending substantially throughout the entire height of said drying chamber.

7. A drying kiln, comprising a drying chamber, a heatin chamber located at one side of said drying chamber, a coolin chamber located at the opposite side of sai. drying chamber, partitions separating said chambers and containingdistributed apertures arranged to permit air to flow from said heating chamber to said cooling chamber in a uniformly distributed current throughout the area of said drying chamber, 7

a return air passage below said drying chamber connecting said cooling chamber with said heating chamber, heating means in said heating chamber and distributed vertically so as to have graduallyreducing heating effect upon the air as it ascends, and cooling means in said cooling chamber. Y

8. Adrying kiln, comprising a drying chamber, a heating chamber located at-one side of said dryin chamber, a cooling chamber located at t e opposite side of said drying chamber, partitions separating said chambers and containing distributed apertures arranged to permit air to flow from said heating chamber to said cooling cham her in a uniformly distributed current throughout the area of said drying chamher, a return air passage below said drying chamber connecting said cooling chamber with saidheating chamber, heating means in said heating chamber, and cooling means in said cooling chamber andextending substantially throughout the entire height of said drying chamber, said cooling means being distributed so that the cooling effect will be more intense at the bottom than at the top of said cooling chamber.

9. In a drying kiln, the combination of a pair of drying chambers located one beside another, a common heating chamber located between them, coolin chambers located at the sides of said drying chambers opposite said' common heating chamber, return air passages connecting said cooling chambers with saidcommon heating chamber, means for heating the air in said heating chamber, and means for cooling it in said cooling chambers, partitions, separating adjacent chambers and having therein distributed air passages arranged to permit the air to 'flow in uniformly distributed currents throughout the area of said drying chambers, the

partitions between said heating and, drying chambers being provided with means for preventing the radiation of heat fromsaid heating means into said drying chambers.

10. In a drying -kiln 'of the class. de-

scribed, the combination of a heating cham-- ber, a cooling chamber, a drying chamber between said heating and cooling chambers, Y

and a return air passage outside of said dryand heating chambers, a condenser in sai cooling chamber, and means providing an inclined surface below said condenser .and sloping downwardly from said cooling chamber toward said passage, said surface having a gutter formed thereinand extending transversely to the direction of flow of the air along said surface, the parts of said surface which are at each side of'said gutter being in substantial alinement with each other, whereby deflection of the airout of a direct course by said gutter will be avoided.

11. A drying kiln, comprising heating, drying and cooling chambers located side by side and substantially co-extensive in the lengthwise direction, a partition separating said heating and drying chambers and having a multiplicity of air passages connecting said chambers and distributed throughout the, area of said partition and being upwardly inclined from said heating. chamber at their mg chamber and connecting said coolin inlet ends and being downwardly inclined toward said drying chamber at their outlet ends, and a return air passage connecting said cooling and heating chambers.

12. A drying kiln, comprising heating,

-through said passages, and a return air passage eonnectingsaid cooling and heating chambers.

13. A kiln of the class described, comprising a building having heating, drying and cooling spaces located side by side, a return air passage connecting said heating and cooling spaces below said drying space, and means interposed between said heating and cooling spaces and providing a multiplicity of air passages adapted to cause theair to flow in a substantially horizontal direction through said drying space, all being arranged to provide a continuous circulation of air by gravity.

14. A kiln of the class described, comprising a building having heating, drying and coolingspaces located side by side cooling means distributed in said cooling space throughout substantially the entire height of said dryin space, a return air passage connecting sa d heating and cooling spaces below said drying space, and means interposed between said heating and cooling spaces and providing a multiplicity of air passages adapted to cause the air to flow in a substantially horizontal direction through said drying space, and all being arranged to provide a continuous circulation of air by.

gravity.

, gust 1910.

CHARLES fA; WENBORNE.

Witnesses: EUGENE A. RUMMLER,

EDWIN PHELPS. 

